Metadata Report for BODC Series Reference Number 1097124
Metadata Summary
Problem Reports
Data Access Policy
Narrative Documents
Project Information
Data Activity or Cruise Information
Fixed Station Information
BODC Quality Flags
SeaDataNet Quality Flags
Metadata Summary
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Problem Reports
No Problem Report Found in the Database
AMT19 flow-through bio-optical Data Quality document
Data Quality Report
On the whole the data provided were of good quality. Some isolated data points were converted to the absent data value and flagged accordingly where the values were not considered within a reasonable range for the parameters. There were short periods on a few days where all data from TEMPSU01, PSALSU01, CPHLUT01 and BS532VSF have been flagged suspect. The data values have not been changed but users should apply their discretion when using these data. These periods occur in the afternoon about the time of the solar noon station. It is possible ship's non-toxic supply has been affected by the use of the ship's thrusters used to keep the ship on station introducing bubbles into the water pumped through the system.
During screening procedures, several periods were identified with gaps on the data.
Data Access Policy
Open Data supplied by Natural Environment Research Council (NERC)
You must always use the following attribution statement to acknowledge the source of the information: "Contains data supplied by Natural Environment Research Council."
Narrative Documents
Sea-Bird SBE 19 and SBE 19plus SEACAT Profiler CTDs
The SBE 19 SEACAT Profiler is a self-contained, battery powered, pumped CTD system designed to measure conductivity, temperature, and pressure in marine or fresh water environments to depths of 10,500 meters. It was replaced by the SBE 19plus model in 2001. An updated version of this instrument is the SBE 19plus V2, which incorporates an electronics upgrade and additional features, with six differentially amplified A/D input channels, one RS-232 data input channel, and 64 MB FLASH memory.
The standard CTD unit comes with a plastic housing (rated to 600 m), although this can be replaced by titanium housing for depths up to 7000 m. It is typically used for CTD profiling although a conversion kit is available for mooring deployments. The CTD can also be attached to an SBE 36 CTD Deck Unit and Power/Data Interface Module (PDIM) for real-time operation on single-core armored cable up to 10,000 m.
Specifications
| Parameter | SBE 19 | SBE 19plus |
|---|---|---|
| Temperature | Range: -5 to +35 °C Accuracy: 0.01 °C Resolution: 0.001 °C Calibration: +1 to +32 °C* | Range: -5 to +35 °C Accuracy: 0.005 °C Resolution: 0.0001 °C Calibration: +1 to +32 °C* |
| Conductivity | Range: 0 to 7 S m-1 (0 to 70 mmho cm-1) Accuracy: 0.001 S m-1 Resolution: 0.0001 S m-1 Calibration: 0 to 7 S m-1. Physical calibration over the range 1.4 - 6 S m-1* | Range: 0 to 9 Sm-1 Accuracy: 0.0005 Resolution: 0.00005 (most oceanic waters, resolves 0.4 ppm in salinity); 0.00007 (high salinity waters, resolves 0.4 ppm in salinity); 0.00001 (fresh waters, resolves 0.1 ppm in salinity) Calibration: 0 to 9 S m-1. Physical calibration over the range 1.4 - 6 S m-1* |
| Strain gauge pressure sensor | Range: 0 to100, 150, 300, 500, 1000, 1500, 3000, 5000, 10000 or 15000 psia Accuracy: 0.25% of full scale range (100 - 1500 psia); 0.15% of full scale range (3000 - 15000 psia) Resolution: 0.015% of full scale Calibration: 0 to full scale in 20% steps | Range: 0 to 20, 100, 350, 1000, 2000, 3500 or 7000 m Accuracy: 0.1% of full scale range Resolution: 0.002% of full scale range Calibration: ambient pressure to full scale range in 5 steps |
*Measurements outside this range may be at slightly reduced accuracy due to extrapolation errors.
Options and accessories
Additional sensors can be attached to the CTD, including:
- high accuracy Paroscientific Digiquartz pressure sensor (depth range 0 to 20, 60, 130, 200, 270, 680, 1400, 2000, 4200, 7000 or 10500 m; accuracy 0.02% of full scale; resolution 0.0025% of full scale)
- Dissolved Oxygen (SBE 43 DO Sensor)
- pH* (SBE 18 pH Sensor or SBE 27 pH/ORP Sensor)
- fluorescence
- radiance (PAR)
- light transmission
- optical backscatter (turbidity)
The standard SBE 5M pump may be replaced by an SBE 5P (plastic housing) or 5T (titanium housing) pump for use with dissolved oxygen and/or other pumped sensors. Further details can be found in the manufacturer's SBE 19plus V2 instrument specification or theSBE 19 andSBE 19 plus user guides.
WET Labs WETStar Fluorometers
WET Labs WETStar fluorometers are miniature flow-through fluorometers, designed to measure relative concentrations of chlorophyll, CDOM, uranine, rhodamineWT dye, or phycoerythrin pigment in a sample of water. The sample is pumped through a quartz tube, and excited by a light source tuned to the fluorescence characteristics of the object substance. A photodiode detector measures the portion of the excitation energy that is emitted as fluorescence.
Specifications
By model:
| Chlorophyll WETStar | CDOM WETStar | Uranine WETStar | Rhodamine WETStar | Phycoerythrin WETStar | |
|---|---|---|---|---|---|
| Excitation wavelength | 460 nm | 370 nm | 485 nm | 470 nm | 525 nm |
| Emission wavelength | 695 nm | 460 nm | 530 nm | 590 nm | 575 nm |
| Sensitivity | 0.03 µg l-1 | 0.100 ppb QSD | 1 µg l-1 | - | - |
| Range | 0.03-75 µg l-1 | 0-100 ppb; 0-250 ppb | 0-4000 µg l-1 | - | - |
All models:
| Temperature range | 0-30°C |
|---|---|
| Depth rating | 600 m |
| Response time | 0.17 s analogue; 0.125 s digital |
| Output | 0-5 VDC analogue; 0-4095 counts digital |
Further details can be found in the manufacturer's specification sheet, and in the instrument manual.
WETLabs ECO-VSF Optical Backscatter Meter
The ECO-VSF is a scattering meter designed to measure the angular distribution of scattered radiation of the backward hemisphere. The instrument measures optical scattering at three angles (100°, 125° and 150°), providing the shape of the Volume Scattering Function (VSF) throughout the backscattering region. Interpolation and extrapolation are used to determine scattering at intermediate angles. It also provides the total backscatter coefficient between 90° and 180° by integration and extrapolation.
The ECO-VSF comes in five versions, with a variety of power options, sampling strategies and anti-fouling capabilities:
- The standard ECO-VSF configuration provides an RS-232 serial output with 4000-count range and can be programmed for continuous operation or periodic sampling.
- The ECO-VSF(RT) provides an RS-232 serial output with 4000-count range and can be programmed for continuous operation.
- The ECO-VSFS adds anti-fouling capabilities to the standard ECO-VSF.
- The ECO-VSFB is a self-recording version of the ECO-VSF with internal batteries for autonomous operation.
- The ECO-VSFSB adds anti-fouling capabilities to the ECO-VSFSB.
The specifications below are common to all versions.
Specifications
| Wavelength | 470, 532 or 660 nm |
| Sensitivity | 1.24x10-5 |
| Typical range | ~ 0.0012-5 m-1 |
| Linearity | 99 % R2 |
| Temperature range | 0-30° |
| Depth rating | 600 m (standard) |
| Sample rate | up to 8 Hz |
| Pressure sensor | optional |
| Temperature sensor | optional |
Further details can be found in the manufacturer's specification sheet.
WETLabs ac-9 and ac-s Spectral Absorption and Attenuation Meters
The WETLabs ac-9 and ac-s meters measure the spectral transmittance and spectral absorption of water, allowing determination of absorption and beam attenuation coefficients. The instruments incorporate a flow-through system and a dual path configuration that permits concurrent measurement of both coefficients along a 25 cm path. The ac-9 provides measurements at nine wavelengths in the range 412-715 nm, whereas the ac-s provides measurements at >80 wavelengths from 400-730 nm.
Specifications
| Parameters | ac-9 | ac-s |
|---|---|---|
| Temperature range | 0-30 ° | 0-30 ° |
| Rated depth | 500 or 5000 m | 500 m |
| Spectral range | 412-715 nm | 400-730 nm |
| Band-pass | 10 nm per channel | 15 nm per channel |
| Pathlength | 25 cm (optional 10 cm) | 25 cm (optional 10 cm) |
| Beam cross-section | 8 mm dia. (nominal) | 8 mm dia. (nominal) |
| Linearity | >=99 % R2 | >=99 % R2 |
| Wavelength output | 9 | 80-90 in 4 nm steps |
| Accuracy | ±0.01 m-1 | ±0.01 m-1 |
| Dynamic range | 0.001-10 m-1 | 0.001-10 m-1 |
Further details can be found in the manufacturer's specification sheet.
AMT19 flow-through bio-optical Instrumentation Description
The instruments used to collect the underway data were:
- SeaBird- temperature and salinity (fact sheet)
- WETLabs Wet Star- chlorophyll fluorescence (fact sheet)
- WETLabs ECO-VSF- particle backscattering (fact sheet)
- WETLabs ac-9- particle absorption and attenuation (fact sheet)
AMT19 flow-through bio-optical Processing
BODC Data Processing Procedures
A file was submitted to BODC containing data from MicroSAS radiometer merged with underway data. The archived file was given the BODC's accession number BGL100197, which includes two different dataset IDs (one for the radiometer parameters and the other for the underway data). The following parameters were supplied for the underway measurements: temperature, salinity, chlorophyll-a, backscattering coefficient, absorption and attenuation coefficients'. Additional metadata was provided, and these included date, time, latitude and longitude obtained through the ship's GPS stream.
No unit conversions were necessary as all the parameters were provided in the same units as in the BODC Parameter Dictionary.
A parameter mapping table is provided below;
| Originator's Parameter | Description | Units | BODC Parameter Code | Description | Units | Comments |
|---|---|---|---|---|---|---|
| lat | Latitude, as mentioned on the originator's file | degrees | ALATGP01 | Latitude north (WGS84) by unspecified GPS system Global Positioning System (receiver type unspecified) | degrees | - |
| lon | Longitude, as mentioned on the originator's file | degrees | ALONGP01 | Longitude east (WGS84) by unspecified GPS system Global Positioning System (receiver type unspecified) | degrees | - |
| bbp532 | Backscattering coefficient of particles(*) | m-1 | BS532VSF | Attenuance due to backscatter (532nm wavelength) in the water body by scattering photometer and calibration to read zero in clear water with computation from volume scatter data | m-1 | NA |
| agp | Absorption Coefficient of Gelbstoff + particles(*) | m-1 | ABSPXAC9 | Light absorbance (unspecified single wavelength) by the water body by transmissometer and calibration to read zero in clear water | m-1 | NA |
| ag | Absorption Coefficient of Gelbstoff(*) | m-1 | ABSULT01 | Light absorbance (unspecified single wavelength) per unit length of the water body dissolved plus reactive particulate <0.2 µm by transmissometer and calibration to read zero in clear water | m-1 | NA |
| cgp | Absorption Coefficient of Gelbstoff + particles(*) | m-1 | ATTNXAC9 | Attenuance (unspecified single wavelength) per unit length of the water body by transmissometer and calibration to read zero in clear water | m-1 | NA |
| wavelength | Wavelength(*) | nm | LAMBIN01 | Wavelength of electromagnetic radiation measurement | nm | NA |
| Sal | Salinity | - | PSALSU01 | Practical salinity of the water body by thermosalinograph and computation using UNESCO 1983 algorithm and NO calibration against independent measurements | - | NA |
| Temp | Water temperature | degrees Celsius | TEMPSU01 | Temperature of the water body by thermosalinograph and NO verification against independent measurements | degrees Celsius | NA |
| Chl | Fluorometrically/spectrophotometrically-derived chlorophyll a(*) | mg m-3 | CPHLUT01 | Concentration of chlorophyll-a {chl-a} per unit volume of the water body [particulate phase] by through-flow fluorometer plumbed into non-toxic supply and calibration against sample data | mg m-3 | NA |
Parameters' marked with (*) are described on the following link: Standardized Field Names and Units for SeaBASS files
AMT19 flow-through bio-optical data
Originator's Protocol for Data Acquisition and Analysis
The underway system operated semi-continuously with water from the ship's non-toxic supply at a rate of 4 L min-1. Every five to seven minutes the following parameters were measured: temperature, salinity, chlorophyll fluorescence and total backscattering at 532 nm. Every two minutes absorption and attenuation coefficients were measured at nine different wavelengths on unfiltered and 0.2 µm filtered water.
The TSG used the manufacturer's calibrations to produce salinity and temperature. The fluorometer was calibrated using discrete chlorophyll measurements made from the non-toxic supply and the surface CTD bottle samples.
References Cited
N/A
Project Information
The Atlantic Meridional Transect - Phase 2 (2002-2006)
Who was involved in the project?
The Atlantic Meridional Transect Phase 2 was designed by and implemented by a number of UK research centres and universities. The programme was hosted by Plymouth Marine Laboratory in collaboration with the National Oceanography Centre, Southampton. The universities involved were:
- University of Liverpool
- University of Newcastle
- University of Plymouth
- University of Southampton
- University of East Anglia
What was the project about?
AMT began in 1995, with scientific aims to assess mesoscale to basin scale phytoplankton processes, the functional interpretation of bio-optical signatures and the seasonal, regional and latitudinal variations in mesozooplankton dynamics. In 2002, when the programme restarted, the scientific aims were broadened to address a suite of cross-disciplinary questions concerning ocean plankton ecology and biogeochemistry and the links to atmospheric processes.
The objectives included the determination of:
- how the structure, functional properties and trophic status of the major planktonic ecosystems vary in space and time
- how physical processes control the rates of nutrient supply to the planktonic ecosystem
- how atmosphere-ocean exchange and photo-degradation influence the formation and fate of organic matter
The data were collected with the aim of being distributed for use in the development of models to describe the interactions between the global climate system and ocean biogeochemistry.
When was the project active?
The second phase of funding allowed the project to continue for the period 2002 to 2006 and consisted of six research cruises. The first phase of the AMT programme ran from 1995 to 2000.
Brief summary of the project fieldwork/data
The fieldwork on the first three cruises was carried out along transects from the UK to the Falkland Islands in September and from the Falkland Islands to the UK in April. The last three cruises followed a cruise track between the UK and South Africa, only deviating from the traditional transect in the southern hemisphere. During this phase the research cruises sampled further into the centre of the North and South Atlantic Ocean and also along the north-west coast of Africa where upwelled nutrient rich water is known to provide a significant source of climatically important gases.
Who funded the project?
Natural Environment Research Council (NERC)
Data Activity or Cruise Information
Cruise
| Cruise Name | JC039 (AMT19, JC040) |
| Departure Date | 2009-10-13 |
| Arrival Date | 2009-12-01 |
| Principal Scientist(s) | Andrew Rees (Plymouth Marine Laboratory) |
| Ship | RRS James Cook |
Complete Cruise Metadata Report is available here
Fixed Station Information
No Fixed Station Information held for the Series
BODC Quality Control Flags
The following single character qualifying flags may be associated with one or more individual parameters with a data cycle:
| Flag | Description |
|---|---|
| Blank | Unqualified |
| < | Below detection limit |
| > | In excess of quoted value |
| A | Taxonomic flag for affinis (aff.) |
| B | Beginning of CTD Down/Up Cast |
| C | Taxonomic flag for confer (cf.) |
| D | Thermometric depth |
| E | End of CTD Down/Up Cast |
| G | Non-taxonomic biological characteristic uncertainty |
| H | Extrapolated value |
| I | Taxonomic flag for single species (sp.) |
| K | Improbable value - unknown quality control source |
| L | Improbable value - originator's quality control |
| M | Improbable value - BODC quality control |
| N | Null value |
| O | Improbable value - user quality control |
| P | Trace/calm |
| Q | Indeterminate |
| R | Replacement value |
| S | Estimated value |
| T | Interpolated value |
| U | Uncalibrated |
| W | Control value |
| X | Excessive difference |
SeaDataNet Quality Control Flags
The following single character qualifying flags may be associated with one or more individual parameters with a data cycle:
| Flag | Description |
|---|---|
| 0 | no quality control |
| 1 | good value |
| 2 | probably good value |
| 3 | probably bad value |
| 4 | bad value |
| 5 | changed value |
| 6 | value below detection |
| 7 | value in excess |
| 8 | interpolated value |
| 9 | missing value |
| A | value phenomenon uncertain |
| B | nominal value |
| Q | value below limit of quantification |
